Hocotatians are the sapient inhabitants of planet Hocotate. They are about the size of a nickel, and appear to be more advanced than humans, and having superior, or at least equal intelligence. One Hocotatian, Captain Olimar, is the protagonist of the Pikmin Series of Games. He discovered the Pikmin on a planet which is strongly implied to be Earth, after he had to land there because his ship was hit by an meteorite.
The Currency of Hocotate is called Poko. The Hocotatian society is much like Earth's human society.
Although little is known about the exact origin of the Hocotanians, we do a little. Namely, they did not evolve, as life on Earth did, from the planet itself. Instead, they came from the "sea of stars" and return there when they die. Olimar briefly mentions this strange life cycle in one of his Journal entries during the events of Pikmin 1.
"My people were borne out of the sea of stars to come down to Hocotate, and when we complete out lives, we return to the great ocean of stars. But since these Pikmin come from the depths of the soil, surely, to the soil they shall return. How very poetic-while it is all alien to me, the basic premise is universally beautiful." -Captain Olimar
Knowing that the Pikmin universe is contained within the Mario universe/multiverse, it is entirely possible that this "sea of stars" is a reference to Lumas and Rosalina. Because Lumas are responsible for creating everything in the Mario universe, this would, essentially, make Hocotanians direct descendants of the stars themselves.
This is further supported by the events of the Yoshi Island series, in which a Hocotanian (possibly Olimar) is collected by Kamek's minions, during Bowser Jr's search for the Star Children.
Much like with their origin, little is known about Hocotanian biology. We do know that they are approximately 2cm (3/4 in.) tall, and around 1 unit in weight. They do not breathe oxygen, as it is considered a toxic gas to them (confirmed in the bad ending of Pikmin 1), although we do not know what they use as a substitute. Hocotanians are shown to be extremely durable (although this is probably also based on their suit technology), as Olimar and Louie both showed the ability to fall from great heights and survive unharmed. Although enemies/hazards in the games do consistently injure them, the worst that happens is that they lose consciousness. This includes being crushed, burned, electrocuted, bitten, and stabbed by creatures many times their size.
According to notes in Pikmin 1, Hocotanians can swim in space. Olimar's ship comes equipped with a "space float" which is supposed to help him do so. It is unknown how they do this, though their origin may have some ties to it.
Hocotanians are characterized by their durable, impressive space suits. Although Olimar and Louie wear suits that appear to double as uniforms, the President of Hocotate Freight's suit is just that; a suit, with a helmet on it. This seems to indicate that Hocotanian clothing is airtight and made of extremely durable unknown materials.
The suits, as of Pikmin 2, is notable for
1) Being airtight and water resistant
2) Has the properties of rubber, and resistant to electricity
3) Is flame retardant (made of an unknown material)
4) Somehow streamlined and resistant to air pressure
5) Equipped with a rocket powered fist, which allows Hocotanians to actually damage enemies fairly effectively
6) Equipped with an automatic teleporter, which withdraws the Hocotanian to safety should their suit sustain too much damage. This seems to be more a property of the ship itself, meaning damaging the suit has no effect on the teleporter.
7) Short range communication. Hocotanian suits can communicate from across entire levels with ease, either with the ship or with other members of the party. The full range is unknown.